IDBFactory.cmp() - Web APIs

The cmp() method of the IDBFactory interface compares two values as keys to determine equality and ordering for IndexedDB operations, such as storing and iterating.

Note: This feature is available in Web Workers.

Note: Do not use this method for comparing arbitrary JavaScript values, because many JavaScript values are either not valid IndexedDB keys (booleans and objects, for example) or are treated as equivalent IndexedDB keys (for example, since IndexedDB ignores arrays with non-numeric properties and treats them as empty arrays, so any non-numeric arrays are treated as equivalent). This throws an exception if either of the values is not a valid key.

Syntax

var result = indexedDB.cmp(first, second);

Parameters

first: The first key to compare.
second: The second key to compare.

Return value

An integer that indicates the result of the comparison; the table below lists the possible values and their meanings:

Returned value	Description
-1	1st key is less than the 2nd key
0	1st key is equal to the 2nd key
1	1st key is greater than the 2nd key

Exceptions

This method may raise a DOMException of the following types:

Attribute	Description
`DataError`	One of the supplied keys was not a valid key.

Example

var a = 1;
var b = 2;
var result = window.indexedDB.cmp(a, b);
console.log( "Comparison results: " + result );

Specifications

Specification	Status	Comment
Indexed Database API 2.0 The definition of 'cmp()' in that specification.	Recommendation
Indexed Database API Draft The definition of 'cmp()' in that specification.	Recommendation

Browser compatibility

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`cmp`	Chrome Full support 24 Full support 24 No support 23 — 24 Prefixed Prefixed Implemented with the vendor prefix: webkit	Edge Full support 12	Firefox Full support 16 Full support 16 No support 10 — 16 Prefixed Prefixed Implemented with the vendor prefix: moz	IE Partial support 10	Opera Full support 15	Safari Full support 7	WebView Android Full support Yes Full support Yes No support ? — ? Prefixed Prefixed Implemented with the vendor prefix: webkit	Chrome Android Full support 25	Firefox Android Full support 22	Opera Android Full support 14	Safari iOS Full support 8	Samsung Internet Android Full support 1.5

Legend

Full support: Full support
Partial support: Partial support
Requires a vendor prefix or different name for use.: Requires a vendor prefix or different name for use.